This invention relates to binders for capturing loose-leaf pages, and in particular to an improved ring mechanism for opening and closing binders.
A loose-leaf binder retains loose-leaf pages, such as hole-punched papers, in a file or notebook. It features a ring mechanism having ring members for retaining the papers which may be selectively opened to add or remove papers, or closed to retain papers while allowing them to be moved along the ring members. Levers are typically provided on both longitudinal ends of the loose-leaf binder for moving the ring members between open and closed positions.
One drawback to loose-leaf binders of the prior art is that the ring mechanisms typically include rough or sharp edges projecting axially from longitudinal ends of an elongate plate which mounts the other components of the ring mechanism. When the elongate plate is cut from sheet metal, upper and lower edges project outwardly from each longitudinal end of the elongate plate. Longitudinal end margins of the elongate plate, including these cut edges, are typically pressed into flatwise engagement with one another to capture movable levers mounted at the longitudinal ends of the ring mechanism. The exposed edges continue to project outwardly and can snag clothing, scratch nearby items and may feel abrasive against a user's skin when operating the ring members. Other designs have attempted to address these undesirable attributes. For example, one such design has an upper surface that extends axially beyond the lower edge. The projecting portion is folded down so that it captures the lever at the longitudinal end of the ring mechanism and presents a blunt surface in a longitudinal direction. The projecting portion essentially provides a barrier covering the edges of the lower surface of the elongate plate. This design also fails to avoid the ill-effects noted above because small items may still become caught under the edge of the folded down projecting portion, and because the manufacture of such a ring mechanism is more complex. It is thus desirable to construct a binder wherein the formation and orientation of such edges minimizes these ill-effects.